Method of making projectiles



Dec. 7, 1943.

T. F. wr-:RME: n 2,336,143

METHOD OF MAKING PROJECTILES Filed Jan. 4, 1941 INVENTOR Tggej? pr'me #waf- WV l AGEN -making a jacketed projectile.

Patented Dec. 7, 1943 UNIT-eo `sfr/iras 'TENT ortie l 2,336,143 e METHOD oF-MAKING PRorEcrrLEs Tage F. Werme, Fairiield, Conn., assigner to Remington Arms Company Inc.,`a.corporaton of Delaware I Application January 4, 1941, Serial No; 373326 2 claims. (onze-1.23)

"an autogenously "welded copper jacket thereon.

A further object is to form an autogenously welded copper jacketed projectile by cutting a com; posite rod substantially into projectile lengths and forming such lengths intothe shape of projectiles. A further object is to provide an improved jacketed projectilecomprising al copper jacket autogenously welded to a steel core and having a tapered steel ogive.A A still further object is to provide an improved metal-cased projectile comprising va steel core, a copper jacket autogenously welded thereon, and having suitable filling metals sealed at least in one end of the core by swaging down the copper jacket. A still further object is to forma metal-cased projectile by spinning a taper or ogive on one end of a suitable length of autogenously welded copper jacketed steel rod. Other objects, features and ad?- vantages of the invention not already mentioned will be hereafter disclosed. Y

As now practiced, the art of making jacketed projectiles is carried out by processes whichrequire a multiplicity of separate operations which, 'as is well known, are characterized by steps comprising first alternate drawings' and annealings "of the jacket disc until it is formed in the shape c f an elongated cup and "then subsequently inserting a separately formed slug or core intothe prepared `jacket. Autom''aticmachinery employel -ing sets of co-operating punches and .dies has been developed to. speed up these operations, but suchrmachinery isy complicated,Y costly andv subject to frequent repair. "Eurthermore, the Vvery nature of the methods used requires at least six or seven separate operations forthe vformation of a completed bullet and these represent inner-'- ent time-wasting and prent-consumingr disadvantages.

Attempts have been made also to manufacture jacketed projectiles using cut-lengths of a cornposite rod comprising a steel core and a galvanic or electrolytically deposited film-coating of some non-ferrous metal, preferably copper. However this'method has proven impracticable because the eost'of electrolytically depositing a coating of copper sufficiently thick to possess the requisites of a jacket'has been prohibitive. As is understood by those skilled in this art, the purpose of the jacket is to act in part as a lubricant between the bullet and the rifle barrel; furthermore,r the 'jacket must-be suiliciently thick to be positively grooved by the barrel rifling, to sustain a relatively deep cannelure without exposing the surface of the steel core, and capable of being swaged so as to cover the exposed ends of the steel core and Vto form an armor-piercing point. yIt is evidentthat the galvanic deposition of a jacket of Ycopper sufliciently thick to meet the above conditions is` not onlyvv exceedingly expensive but time-consuming. A further difiiculty with a p'rojectile 'made by a process using a galvanic coated rod is thatthe best union that can be formed in this manner, so far as known, is a mere adhesion or stckingtogether of the twometals, and not va true cohesion. In a way, it may be said that 4thev coating and attack the metal beneath. `It is evident that this is an undesirable feature for the longevity and storage of bullets. Conseduently, the production of jacketed projectiles lusin'g electrolytically or galvanic coated rods may befairly regarded as unsatisfactory.

The present invention is the successful solution of the problem of making projectiles 'from com posite rods. In lthis case, the composite rods are formedffrom an ingot' comprising a steel core 'having' arelatvely thickfcoating or jacket of a v'n''on-ferrous4 metal autogenously welded thereon. f'Ifhjtis to say, the nonfero'us metal,v preferably "copperQwhile at a Yso-calleol super molten 'tem- 'perature israllowed 'to contact with the surface'of Ithe steel vcoreand is held 'against the surface thereof during solidication, the temperature of the molten metal being allowed to fall as soon as 'a true wetting is eifected, whereupon a union of the unlike metals is formed vwhich is absolutely. permanent and is as strong as a true weld, the metals so joined being inseparable by change of temperature or by shock. The union thus produced is equivalent to what, in the case of united bodies of steel and iron, is called a weld, and, whenreferring to the union of unlike metals,

-is hereinafter termed an autogenous weld or an autogenous union, the compound rod so produced being capable of being rolled or drawn to any desired extent without separation of the jacket metal from the core and with substantial maintenance of the original thickness of the coating relative to the thickness of the core.

In the drawing:

Fig. 1 shows a plan view of a semi-jacketed ball projectile partly in cross section.

Fig. 2 shows a cross section of a piece of composite rod from which the projectile of Fig. l was made as indicated by the dotted lines and heavy cross sectioned areas.

Fig. 3 shows a cross section of a pistol bullet having a blunt steel ogive.

Fig, 4 shows a cross section of a jacketed projectile having a hollow nose.

Fig. 5 shows a cross section ofa piece of com.- posite rod during the initial stages in. the construction of the projectile of Fig. 4.

Fig.v 6 is a modification of the bullet shown in Fig. 4 showing a metal iiller in the hollow nose.

Fig. '7 is the cross section of an armor-piercing projectile.

Fig. 8 is a cross section of jacketed steel tracer bullet.

Fig. 9 shows an autogenously welded composite rod partly in cross section marked with suitable projectile lengths.

Referring to Fig'. 1, the numeral I represents, in general, a semi-jacketed projectile suitably secured in the neck of the cartridge case 2 by swaging or crimping. the neck 3 into the cannelure 4 formed' in the projectile jacket 5. The jacket comprises a copper or gilding metal cover autogenously welded to the steel core 6; it will be understood, however, that other non-ferrous metals such as cuprous alloys (bronze, brass, etc.) or silver, aluminum, aluminum alloys, etc., may be used instead of copper, and thatthe steel core may be a soft steel for so-called ball cartridges, or a tungsten or tool steel adaptable for armorpiercing projectiles. Lines 1, 'I represent the longitudinal limits of the copper jacketing of the steel core 5. As shown by the cross section portion of the drawing, the steel core 6 `defines substantially the entire body of the projectile, that portion of the core between the lines 1, 1 being covered by the copper jacket 5 autogenously welded thereto and thosel portions 8 and 9 of the core which extend beyond the jacket comprising the steel taper or ogive and steel boat-tail portions respectively. If preferred the steel ogive may have the same hardness characteristics as the core of the projectile but it is understood to be withinthe scope of this invention to heat treat the steel ogive for obtaining a taper having hardness characteristics suitable for armor-piercing purposes, etc. As illustrated, this projectile is manufactured simply by forming, as by turning on a lathe or other equivalent tool, a suitable length of jacketed steel rod such as indicated by numeral l of Fig. 2, the bare or unjacketed steel of the ogive 8 and tail 9 portions being exposed simultaneously with the removal of the excess copper-jacket and steel-core material indicated by the heavily cross-sectioned areas I2 of Fig. 2, during the formation of the ogive and boat-tail. The cannelure 4 can be readily formed Von the projectile while it is in the lathe, suitable grooving or spinning tools beingadapted for this purpose.

Fig. 3 shows a j'acketed steel pistol bullet adapted for piercing bullet-proof glass, light armor, engine blocks, etc. The projectile comprises a steel core I4, preferably a soft steel, although a tungsten steel may be used, jacketed by an autogenously Welded covering of copper or gilding metal I5. The copper jacket is formed with a cannelure I6 for the reception of the crimped neck I1 of the cartridge case I8. The bullet has a relatively blunt steel ogive I9, the latter being formed during production by turning off the excess jacketing and core metal, as explained above, to form an obtunding steel taper.

An alternative form of projectile shaped from y ar length of autogenously welded copper jacketed steel rod is shown in Fig. 4. This projectile is of the so-called hollow nosed type. i. e., the copper jacket of the rod is swaged or spun down to form a hollow taper 2U extending beyond the end of the steel core vpiece 2l. Fig. 5 shows a length of jacketed rod during the initial steps in the construction of the bullet in Fig. 4; one end of the rod has been drilled out as at 24, the diameter of the hole being equal to the diameter of the steel core 2I so that the copper jacketing of the core becomes, in effect, a thin sleeve or collar extending beyond the enelr 22'01e the steel core 2 I. The taper of the projectile is made by swaging or spinning down the copper sleeve-like portion 25 to form la suitable hollow ogive 20 (see Fig. 4). The rear end of the projectile is formed simply as a flat plane 26 cut ofi'. square with the length of the composite rod and the usual cannelure 23 is tooled into the outside of the copper jacket for securing the bullet in the mouth of a cartridge case.

An obvious modification of the hollow nose type of bullet is the mushrooming type of projectile shownv in Fig. 6. This projectile differs from the one shown in` Fig. 4 only in having a filler material 28 suitably secured in the hollow ogive 29. Th method of making this bullet is substantially similar to the above-described method, the jacketed rod being first provided with a drilled cavity or seat 30. Thereafter the cavity 30 is lilled` with a suitable ller material, in this case an alloy of lead and antimony, and the taper 29 suitably formed thereover as by any of the well known swaging or spinning operations. It is to be understood that other filler materials can be used. The rear end 32 of the bullet is constructed simply as a flat plane cut 01T at right angles to the length of the composite rod and having no boat-tail shape.

Afurther modification of the bullet illustrated in Fig. 4 is the armor-piercing type of bullet of Fig. '7. This type of projectile is constructed from lengths of tungsten or relatively hard steel rods 35 having a jacket of copper 34 autogenously welded thereon. As is made clear by the drawings, this projectile is of the so-called metalcased type, i. e., the core of the bullet is covered by a metal jacket which extends` from the tailend to the tip end of the ogive of the projectile. In accordance with thisY invention the armorpiercing projectile may be made by the process of spinning a proper taper or ogivey on one end of a suitable length of copper jacketed steel rod. The steel core is thus formed, by any of the well known methods of spinning metals, into a taper 36 concentric with the copper jacket taper 31 as indicated in Fig. 7. The ogive so formed is solid, as distinguished from the hollow nose type of bullet, the core portion of the ogive being integral with the core metal of the body of the projectile. The rear end of the projectile is formed square, i. e., with no boat-tail characteristics and the usual cannelure 38 is tooled into the Ycopper jacket to form suitable means for securing the projectile to a cartridge case.

Fig. 8 shows a tracer bullet constructed from an autogenously welded copper jacketed steel rod. The tracer projectile is used, in many instances, for armor-piercing purposes, as, for example, in modern aircraft, tanks, etc., and hence may be constructed as an armor-piercing bullet of the metal cased type shown in Fig. 7. In the illustrated form, however, the projectile is formed as hereinbefore described with reference to Fig. 1, having a steel taper or ogive 4i! and copper jacket 43. The rear end of the projectile is substantially square as distinguished from a boat-tail end construction and is suitably drilled out for a considerable portion of its length to form a cavity 4I into which is introduced an inflammable filler or tracer composition 42. The usual sealing material (not shown) may be used if desired to seal the tracer composition in place. A suitable cannelure is formed in the copper or gilding metal jacket 63 for effecting the joining of the projectile to a cartridge case.

From the above descriptions taken in connection with the drawing, it is believed that the methods used in making the various types of projectiles have been adequately described for one skilled in the art. As shown in the drawings Fig. 9 represents an autogenously welded copper jacketed soft steel or tungsten steel rod 45, adapted for the manufacture of projectiles from the cut lengths Il), I0, IU. Any of the commonly recognized and well-known methods and tools for cutting, turning, swaging, spinning and drilling may be adapted to the construction of the bullets, but it is not intended by the above discussions to be limited to the particular method outlined, other methods, such as die-forming, being conceivably within the scope of this invention,

As set forth above, this invention represents an improved and successful method of forming steel projectiles by turning, spinning or otherwise 'shaping lengths of autogenously welded copper jacketed steel rods, and is the nal step in the speedy and economical production of steel-cored copper-jacketed bullets of the ball, mushroom, hollow-point or armor-piercing type.

What is claimed is:

l. The method of making a metal cased projectile which comprises the steps of providing a rod of steel having a relatively thick jacket of copper autogenously welded thereon, dividing the rod into parts each substantially equal to the length of a projectile, forming a cavity at one end of each part, and then swaging down the copper jacketing over the end having said cavity to form an ogive.

2. The method of making a metal cased projectile which comprises the steps of providing a rod of steel having a relatively thick jacket of copper autogenously welded thereon, dividing the rod into parts each substantially equal to the length of a projectile, forming a cavity at one end of each part, filling said cavity with a soft metal filler and then swaging down the copper jacketing over the ller to form an ogive.

TAGE F. WERME. 

